Abstract: Our goal is revealing the pollutant presence and evaluating the thermal comfort indexes in indoor environments by means of a simple, flexible, cheap and sensitive device, even for individual use i.e. the parameters may be evaluated directly by the user. The proposed device is an innovative system developed by the Polytechnic of Bari (Italy).There are a lot of risky situations in everyday life at work and home. The main chemical agents causing short-and long-term effects are CO2, NOx, VOC (eg.: alcohol exposure in clinical settings, exhausted gases in industrial plants and formaldehyde in furniture).Even the environmental comfort indexes (temperature and relative humidity) affect the psychological well-being of the worker or the person who lives in a confined environment.
The proposed system is a device for monitoring indoor air quality.The instrument is composed of an acquisition module comprising the sensors and the signal conditioning circuitry, and a data-logger that records the data in an SD memory. For assembling the device the following sensors are provided: LM335 sensors for detecting temperature, TGS2180 for relative humidity, TGS2620 and TGS2602 to monitor VOCs and alcohol, TGS2201 for gases exhausted, TGS4161 for CO2 and TGS2444 for NH3.The criterion for the choice of these sensors was based on the need for covering the greatest range of pollutants to be observed.
The device was tested in a confined work environment for a 5-day period showing very interesting results of feasibility and performance. By analyzing the device-generated data together with the graphs associated to them , it was possible to observe the behavior of the sensors subjected to particular stress (eg.: the use of detergents containing NH3 or VOCs the presence or absence of workers within office).The paper shows all acquired data in graph form.
The main sources of indoor pollution are linked to human activity. It can be of direct production-type (emission of toxic substances), or it may be ascribed to the presence of environmental pollutants from furnishings (glues, solvents, printers, etc.) and cigarette smoke. With respect to article 81/08 of the Italian Consolidated Law on Occupational Safety and Health at work as well as in the framework of prevention and promotion of hygiene/health care issues, our device appears to be feasible with indoor environmental problems resulted from toxic factors. The device can be seen as an integrated part of a more comprehensive system for the assessment of specific risks in the workplace, but it is also useful in resolving potentially dangerous situations coming from environmental discomfort. Further tests on additional sensors, which are specific to the device for detection of background radioactivity (radon), electromagnetic fields at power frequency and radio frequency (PC,phones) and anesthetic gas (Operating rooms) are being carried out and during this test phase many steps forward have been made.